WO2018043634A1 - Carbon-based hydrogen storage material having autocatalytic capability, production method therefor, and hydrogen adsorbing-storing method, hydrogen releasing method, and hydrogen adsorption-storage device using said compound - Google Patents

Abstract

The objective of the present invention is to provide a carbon-based hydrogen storage material having an autocatalytic capability, and a production method therefor. The present invention provides a carbon-based hydrogen storage material having an atomic defect, which is a hydrogen adsorbing-storing hydrocarbon compound having an autocatalysis reaction, wherefrom hydrogen that has been adsorbed and stored within the compound is either released while no heat is absorbed, or released while heat is generated. In addition, provided is a production method for the carbon-based hydrogen storage material having the autocatalytic capability, comprising: preparing a hydrocarbon compound serving as a production starting material for the carbon-based hydrogen storage material; setting the production starting material inside a container under a predetermined partial gas pressure; irradiating the production starting material with an ion beam and then performing annealing under predetermined conditions, thereby forming the hydrocarbon compound having the atom defect; and processing with activated hydrogen the hydrocarbon compound having the atom defect. Also provided is a production method for a hydrogen adsorption-storage device using the carbon-based hydrogen storage material.

Description

Carbon-based hydrogen storage material having autocatalytic ability, production method thereof, hydrogen storage method and hydrogen release method using the compound, and hydrogen storage device

The present invention relates to a carbon-based hydrogen storage material having an autocatalytic function, a method for storing hydrogen using the material, a method for releasing hydrogen stored in the material, and a hydrogen storage device. More specifically, the present invention relates to a carbon-based hydrogen storage material having a specific atomic deficiency and an autocatalytic ability without adding an alkali metal or the like, and a method for producing the same. The present invention also relates to a method for storing hydrogen using the material, a method for releasing hydrogen stored in the material, and a device for storing hydrogen using the material.

The modern life is highly dependent on electrical energy. In supplying such electric energy, fossil fuels, nuclear materials, etc., mainly oil, are often used, but the current situation is that crude oil and nuclear fuel depend on imports from overseas.

On the other hand, it is also known that carbon dioxide emitted by the use of fossil fuels causes a greenhouse effect and causes environmental problems such as global warming. Also, fossil fuel production and prices are unstable due to rising energy demand in emerging countries and the destabilization of local political conditions.

Under such circumstances, hydrogen has been attracting attention as an energy source that does not emit carbon dioxide. Hydrogen is supplied as a by-product in the production process of organic industrial products using chemical reactions, and has the advantage that it is a fuel that maximizes the performance of the fuel cell and that there is no carbon dioxide generation. However, since hydrogen has high reactivity, a technology that can be transported and stored while ensuring safety and a technology that efficiently extracts stored hydrogen are required. As such a technique, for example, a technique of filling a hydrogen tank with gaseous or liquid hydrogen and then transporting the tank (see Patent Document 1, hereinafter referred to as “Prior Art 1”) has been proposed. Further, a technique related to hydride formation and liquefaction or solidification of such hydride (see Patent Document 2, hereinafter referred to as “Prior Art 2”) has been proposed.

Until now, the development of hydrogen storage materials using hydrogen adsorption / desorption reactions in which molecular or atomic hydrogen is adsorbed / desorbed on various carbon materials has been promoted. As the use of the hydrogen storage material, application research to a fuel cell that can be used as a power source for automobiles, business use or business use, or a home use power source is underway. In recent years, technological development for the construction of a hydrogenated society using hydrogen as an energy source has been rapidly advanced.

Examples of such carbon materials include graphite, activated carbon, graphene, nanographene, aromatic hydrocarbons, polycyclic aromatic hydrocarbons, carbon nanotubes, fullerenes, and the like. When the carbon material as described above is used, when a graphite intercalation compound is synthesized by adding an alkali metal to graphite, a hydrogen storage material (hereinafter referred to as “hydrogen storage material”) exhibiting excellent hydrogen storage capacity. Is known), and examples of practical material development are also known (see Non-Patent Document 1, hereinafter referred to as “Prior Art 3”).

In addition, a technique of synthesizing an organic hydride obtained by further hydrogenating an organic molecule such as toluene and using such a compound is also known (see Patent Document 3, hereinafter referred to as “Prior Art 4”).
Furthermore, various carbon-based materials including composite carbon materials have been studied as materials used for liquefying or solidifying hydrides. Among these carbon-based materials, when a substance having a relatively wide graphene surface structure (for example, hydrogenated graphene, graphane, graphon, etc.) is brought into contact with atomic hydrogen, the atomic hydrogen has a relatively large heat of reaction. It is known to constitute a stable adsorption state (on-top type adsorption structure) (see Non-Patent Document 2: hereinafter referred to as “Prior Art 5”).

JP2016-94948 JP2010-254491 JP2015-145347

Conventional technology 1 is a technology for filling a hydrogen tank with gaseous hydrogen, and is excellent in that the increase in weight is only the weight of the tank itself. However, an increase in pressure is inevitable for filling hydrogen with high density. As a result, when oxygen in the air reacts with hydrogen gas and is transported in-vehicle, there is a problem that safety cannot be ensured when involved in an accident. Moreover, since it is unavoidable that the boiling loss occurs, there is a problem that the cost is increased.

Further, the prior art 2 is an excellent technique in that when the hydride is filled in a liquid or solid state and filled in the tank, it can be filled more than in the gas state. However, when the transport distance becomes long, it is essential to cool the entire container, and there is a problem that the stored hydrogen cannot be taken out efficiently.

Conventional technology 3 is an excellent invention in terms of hydrogen storage capacity. However, in many cases, there is a problem that a material having a structure having a low activity energy barrier cannot be constructed unless the activity is improved by using a metal catalyst or the like together. Here, the low activity energy barrier refers to a barrier of 1.5 eV or less having a catalytic function based on a structure made of only a carbon material. This also applies to the dehydrogenation reaction of organic hydride supplied as a practical material, and there is a similar problem when it is assumed that hydrogenated graphene such as graphane or graphon is used.

Conventional technology 4 is excellent in that the organic hydride used for filling can be synthesized in a chemical factory or the like that generates hydrogen, and the liquid / organic hydride is stable and safe. However, since energy is required at the stage of taking out the hydrogen once stored in the organic hydride, for example, there is a problem that a large-scale facility is required to take out the hydrogen stored in the organic hydride.

For this reason, there has been a strong social demand for safe and efficient storage or transport of hydrides, and for efficient removal of stored hydrogen by simple operations.

Conventional technology 5 is an excellent technology in that hydrogen is stably adsorbed. However, when this on-top type adsorption structure is formed, when releasing molecular hydrogen from the surface of this graphene, it is necessary to cross the activity barrier of elimination reaction exceeding 1.51eV. There is a point. If the activity barrier of the elimination reaction exceeds 1.5 eV, high energy is required for releasing hydrogen, and the endothermic reaction results in poor release efficiency.

Carbon-based materials as materials for hydrogen storage materials have the possibility of high-density hydrogen filling utilizing the layered structure unique to graphite-like substances, have a relatively light structure, and maximize the carbon-to-hydrogen ratio. There is an advantage that a method in which easy desorption from the hydride can not be expected while the ratio is up to 1: 1 will be found.

However, even in the method using these material systems, there is a problem that it is difficult to stably adsorb hydrogen only with a pure hydrocarbon material. In addition, there is no known material system that can easily release hydrogen while performing sufficient control at a temperature of 500 ° C. or lower while stably maintaining a hydrogen storage state at room temperature.

For this reason, there has been a strong social demand for a material having a low active barrier composed of only pure hydrocarbon materials, that is, a material having excellent hydrogen storage ability and release ability.

The present invention has been completed under the above circumstances. That is, an object of the present invention is to provide a carbon-based hydrogen storage material having autocatalytic ability and a method for producing the same. Another object of the present invention is to provide a hydrogen storage method, a hydrogen release method, and a hydrogen storage device using the above-described compound.

An embodiment of the present invention is a carbon-based hydrogen-occlusion hydrocarbon compound having an atomic deficiency that has autocatalytic ability and releases the hydrogen occluded in the compound without endotherm or exothermicly. It is a hydrogen storage material. Here, the hydrogen storage hydrocarbon compound is preferably composed only of carbon and hydrogen, and the atomic deficiency is preferably a trihydrogen atom deficient structure (V ₁₁₁ structure).

Further, the hydrogen absorbing hydrocarbon compound is preferably a graphene or nanographene having a V ₁₁₁ structures. The dissociative adsorption activity barrier in the hydrogen storage hydrocarbon compound is preferably less than 2 eV, and more preferably 1.3 eV or less. Moreover, it is preferable that the said hydrogen storage hydrocarbon compound is what can occlude and discharge | release two or more hydrogen molecules per catalyst active point.

Another aspect of the present invention is a method for producing a carbon-based hydrogen storage material having an atomic defect, comprising: preparing a hydrocarbon compound that is a raw material for producing the carbon-based hydrogen storage material; and reaction activity with the hydrocarbon compound Setting the production raw material in a container having a gas partial pressure of 0.5 × 10 ⁻⁷ to 0.5 × 10 ² Pa; and irradiating the hydrocarbon compound with an ion beam at 550 to 650 ° C. for 2 to 5 Annealing for seconds to form a hydrocarbon compound having an atomic defect;

A step of activating hydrogen in the vessel with an arc-shaped (arc-shaped as a geometric shape) filament (hereinafter sometimes referred to as “wire”) at 2,000 to 2,400 ° C .; Exposing the compound to the activated hydrogen at 800 to 1,000 ° C. for 5 to 10 minutes, wherein the carbon-based hydrogen storage material having an atomic deficiency has autocatalytic ability, In the above production method, the hydrogen occluded hydrogen is released without absorbing heat or is released while generating heat.

Here, the lower limit of the hydrogen partial pressure is set to “0.5 × 10 ⁻⁷ ” when the base pressure of the ultra-high vacuum chamber (apparatus pressure before starting the experiment) is generally good. since in is about 0.5 × ^{10 -8,} setting the predetermined condition is by the ^10-7 order. Moreover, it is preferable that the said hydrocarbon compound is graphene or its analog. The ion beam is preferably selected from the group consisting of an argon ion beam, a helium ion beam, a krypton ion beam, and a xenon ion beam, and more preferably an argon ion beam or a helium ion beam. The argon ion beam is preferably irradiated at 80 to 110 eV for 2 to 5 seconds, wherein the desired atomic defect structure is a V ₁₁₁ structure.

Yet another embodiment of the present invention is a method for storing hydrogen, characterized in that the above-described carbon-based hydrogen storage material stores hydrogen at 0.5 × 10 ⁻³ to 15 MPa.
Yet another embodiment of the present invention provides the above-described carbon-based hydrogen storage material in which hydrogen is occluded at 0.5 × 10 ⁻³ to 15 MPa at 0.5 × 10 ⁻⁹ to 0. ⁵ ° C. at 0.5 × 10 ² to 1.5 × 10 ³ ° C. This is a method for releasing hydrogen from a carbon-based hydrogen storage material by heating for 8 × 10 ⁴ seconds. More preferably, the heating temperature is about 50 ° C. to 200 ° C.

Another aspect of the present invention is a hydrogen storage member constructed of the above-described carbon-based hydrogen storage material; a container having a hydrogen inlet / outlet and capable of forming a sealed internal space in a state where the hydrogen storage member is accommodated; A hydrogen storage device, comprising: a pressure control device that controls a pressure in the container; and a temperature control device that controls a temperature in the container; and a safety valve at an inlet / outlet of the hydrogen.

Here, when the hydrogen is stored in the carbon-based hydrogen storage material, the pressure control device controls the pressurization, and the temperature control device controls the temperature in the container so that the hydrogen is stored in the carbon-based hydrogen storage member. Is preferably adsorbed. Moreover, when releasing hydrogen from the carbon-based hydrogen storage material, initially, the hydrogen stored in the carbon-based hydrogen storage member is released by controlling the heating of the container with the temperature controller while maintaining normal pressure. It is preferable.

The pressure control device sets the inside of the container to normal pressure, controls the heating inside the container to start the release of the hydrogen stored in the hydrogen storage member, and after the start of the release, the temperature control device However, it is preferable to control the release rate of hydrogen stored in the carbon-based hydrogen storage material by controlling the temperature in the container.

The hydrogen storage device further includes a voltage application device that applies a voltage between both surfaces of the flat member made of the carbon-based hydrogen storage material and the substrate material, and the voltage application device reverses the polarity of the applied voltage. It is preferable that it is possible.

It is preferable that the device further includes a vibration device that vibrates the flat plate member. Further, the apparatus further includes a light irradiation device that accelerates the release of hydrogen by irradiating the flat plate member with light selected from the group consisting of infrared light, terahertz light, visible light, ultraviolet light, and laser light. preferable.

According to the present invention, there is provided a carbon-based hydrogen storage material that has a low reaction activity barrier for adsorption / desorption reaction and has an autocatalytic function that cannot be obtained with carbon-based materials having other structures.
Moreover, according to this invention, the manufacturing method which can manufacture the carbon-type hydrogen storage material which has the above characteristics simply and efficiently is provided.
Further, according to the present invention, the adsorbed hydrogen can be stably stored at a temperature of about room temperature, and the adsorbed hydrogen can be quickly released in a temperature range of about 180 ° C. to about 1,500 ° C. Thus, a hydrogen storage device is provided that can be used as a storage carrier or transport carrier.

FIG. 1 is a diagram showing the structure of a carbon-based material having a trihydrogen atom deficiency. (A) is a schematic diagram of a three-dimensional model showing the structure of the carbon-based material. (B) is a high-resolution scanning tunneling microscope image when hydrogen is occluded in graphene as an example of the material and then released. FIG. 2 is a diagram showing the structure of a molecule that can be used as the hydrogen material of the present invention. (A) is a schematic diagram of a three-dimensional model, and (B) is a diagram showing a molecular structure in a chemical formula. FIG. 3 is a graph showing a hydrogen atom surface diffusion reaction process from a 4-hydrogen atom-deficient structure that forms a 3-hydrogen atom-deficient structure. (A) to (E) in the figure show the transition states of atoms in the carbon material.

FIG. 4 is a schematic diagram showing the transition state of atoms in the states shown in (A) to (E) of FIG. FIG. 5 is a graph showing an adsorption reaction process of molecular hydrogen on a trihydrogen atom-deficient structure. (A) to (C) in the figure show the transition states of atoms in the carbon material. FIG. 6 is a schematic diagram showing the transition state of atoms in the states shown in (A) to (C) of FIG.

FIG. 7 is a diagram showing the first half of a synthesis route of a _C59 segment having a _V111 structure. FIG. 8 is a diagram showing the latter half of the synthesis route of the _C59 segment having the _V111 structure. FIG. 9 is a diagram showing the first half of a synthesis route of a C ₅₉ segment having n—C ₁₂ H ₂₅ having a V ₁₁₁ structure.

FIG. 10 is a diagram showing the first half of a synthesis route of a C ₅₉ segment having n—C ₁₂ H ₂₅ having a V ₁₁₁ structure. FIG. 11 is a diagram illustrating a synthesis route of graphene having a V ₁₁₁ structure. FIG. 12 is a diagram showing a synthesis route of a C ₁₃₁ segment having a V ₁₁₁ structure.

FIG. 13 is a schematic view showing a hydrogen storage device using the hydrogen storage material of the present invention. FIG. 14 is a schematic diagram showing reaction coordinates and energy fluctuations when hydrogen is desorbed / adsorbed, surface diffused, etc. from the hydrogen storage material of the present invention.

FIG. 15 is an STM image showing a typical atomic defect after sputtering. (A) is the STM image which shows the distribution of the non-passivated atomic defect which exists in the uppermost graphite layer as protrusion of a 3-fold symmetry axis. (B) shows a typical distribution of atomic defects after sputtering of the sample surface. (C) shows two atom-deficient subtypes that are not passivated. FIG. 15 (d) is a topographic line profile of STM across an unpassivated atomic defect.

FIG. 16 is an optical microscope image of an example of the preparation result of single-layer graphene flakes. (A) is an optical microscope image of an as-prepared single layer graphene flake formed on a Si substrate covered with a 285 nm thick SiO ₂ layer. (B) is an optical microscope image of the same graphene flakes after the Au / Cr electrode is attached by photolithography.

FIG. 17 is a diagram schematically showing a cross-sectional view of a structure in which graphene patterned into a nanoribbon shape is placed on a substrate. FIG. 18 is a diagram schematically showing a cross-sectional view of a field effect transistor (FET). FIG. 19 is a diagram (part 1) illustrating the V _bg dependency of a graphene sample.

FIG. 20 is a diagram (part 2) illustrating the V _bg dependency of a graphene sample. FIG. 21 shows the backside voltage dependence of the conductivity when V _bg = +30 V and the original graphene sample was exposed to hydrogen molecules for 5 minutes, 10 minutes, 15 minutes and 30 minutes without exposure. . FIG. 22 shows the backside voltage dependence of conductivity when V _bg = −30 V and the original graphene sample is exposed to hydrogen molecules for 5 minutes, 10 minutes, 15 minutes and 30 minutes without exposure. .

Hereinafter, the present invention will be described in more detail with reference to FIGS. In addition, the same number is attached | subjected to the same member and the overlapping description shall be abbreviate | omitted.

1. Carbon-based hydrogen storage material having atomic deficiency (1) Characteristics and structure of carbon-based hydrogen storage material having atomic deficiency of the present invention The present invention relates to a carbon-based hydrogen storage material having atomic deficiency (hereinafter simply referred to as “hydrogen storage material”). This hydrogen storage material has (1) an autocatalytic reaction, and (2) releases the hydrogen stored in the compound without endotherm, or releases it exothermically. Has characteristics.

The hydrogen storage material of the present invention is composed only of carbon and hydrogen and does not need to contain a metal. This is due to the characteristics of the structure of the substance constituting the hydrogen storage material, which will be described later. The hydrogen storage material of the present invention is preferably graphene having atomic defects, nanographene or other graphenes. There are two types of graphene edge structures: zigzag type and armchair type. Graphene is a combination of graphene bonded together by van der Waals forces.

(2) “Self-catalytic ability” and the like of the carbon-based hydrogen storage material of the present invention The carbon-based hydrogen storage material having an atomic deficiency used in the present invention is a hydrogen storage hydrocarbon compound composed of only carbon and hydrogen. And has a structure that causes a local autocatalytic reaction (hereinafter sometimes referred to as “autocatalytic structure”). Examples of such autocatalytic structures include trihydrogenated atom deficient structures that exist locally in various carbon materials, including compounds having a graphene-like structure, polycyclic aromatic molecules, and other hydrocarbon molecules. (See FIGS. 1A and 2A).

“Autocatalytic reaction” refers to the following reaction. In other words, by activating a substance that absorbs hydrogen (hereinafter referred to as “hydrogen-absorbing substance”), the local structure in the introduced substance changes the dissociated hydrogen atoms and the dissociated hydrogen atoms at the time of hydrogen absorption into the substance. It promotes the reaction of diffusing and occluding to other parts in the interior, and at the time of hydrogen desorption, it promotes the fusion of the occluded hydrogen atoms and induces the desorption of hydrogen molecules. It means a reaction that the hydrogen storage material itself has.

Here, in the above definition, “by activation” means that the local structure on the surface (hereinafter sometimes referred to as “local structure”) is the molecular dissociation and atomic fusion reaction of hydrogen. When it is considered that atomic hydrogen diffusion to or from other parts of the surface (hereinafter sometimes referred to as “inside”) is responsible for occlusion and desorption. This is because a local structure that can be said to cause a catalytic reaction is created without using a metal. Specific examples of such metals include palladium. Further, “autocatalytic ability” means catalytic ability showing an autocatalytic reaction, and is synonymous with “autocatalytic function”. “Autocatalytic structure” means a local structure of a hydrogen storage material having autocatalytic ability.

Hereinafter, the relationship between the trihydrogen atom-deficient structure and the catalytic ability will be described.
The general “catalyst” means that the structure of the catalyst itself is unchanged before and after the reaction, but has a function of increasing the activity of the entire chemical reaction. In the present specification, graphene, nanographene, and related polycyclic aromatic compounds are collectively referred to as “graphene and the like”.

Graphene and nanographene have a honeycomb lattice-like carbon skeleton (arrangement of atoms formed by carbon bonding to each other) formed from sp ² bonds. Hereinafter, such a structure is referred to as a “graphene structure”. In the graphene structure, an atomic deficiency (a defect structure in which one carbon atom that should originally be lost in a complete honeycomb structure) can be introduced.
The above-mentioned atomic defects can also be created by a defect introduction method (a method of knocking out carbon from an array by irradiating ions) by sputtering using ionized inert gas, etc. It can also be created by an introduction method (a method for constructing a defective sequence from the beginning).

Then, by reacting hydrogen in an atomic or molecular state under the condition of setting an appropriate temperature and hydrogen gas partial pressure for each hydrogen state, the introduced atomic vacancy site is 3 A hydrogen atom deficiency (V ₁₁₁ ) can be formed.

In this three-hydrogen atom deficient structure, another hydrogen molecule can be adsorbed, and a five-hydrogen atom deficiency is generated immediately after adsorption. At that time, the bonds between atoms in the original hydrogen molecule are broken and molecular dissociative adsorption occurs. Following this reaction, two of the five hydrogens that make up the pentahydric atom deficiency are adsorbed directly above the carbon in the developing graphene skeleton (adsorption state called on-top type adsorption) As such, a “surface diffusion reaction” (migration) may occur. Here, “migration” refers to changing the adsorption position so as to diffuse on the graphene skeleton. As a result of the movement of two of the adsorbed hydrogen atoms, a trihydrogen atom deficiency is left behind.

When the trihydrogen atom deficiency is restored as a result of hydrogen diffusion, the dissociative adsorption reaction of hydrogen molecules using the trihydrogen atom deficit occurs again, resulting in continuous molecular dissociative adsorption as a whole. That is, since hydrogen dissociative adsorption can be caused continuously on one graphene skeleton, it can be said that the trihydrogen atom deficiency has a catalytic ability for the dissociative adsorption reaction of hydrogen molecules.

Graphene and the like are inactive in a honeycomb lattice-like carbon array composed of six-membered rings, when they have no defects, do not exhibit strong activity against hydrogen molecule adsorption. Here, when the atomic defect structure itself is considered to be a part of the graphene structure, this local atomic structure can be considered as a functional group in a broad sense. That is, by introducing a trihydrogen atom-deficient structure into graphene or the like as described above, the reaction is promoted so that molecular dissociative adsorption of hydrogen molecules proceeds well, and as a result, a large amount of hydrogen can be easily converted into graphene. It can be adsorbed on the skeleton.

Further, when attention is focused on the hydrogen desorption reaction mediated by the above-described 3 hydrogen atom deficiency and 5 hydrogen atom deficiency, this is the reverse reaction of the above hydrogen adsorption reaction. That is, since the above migration occurs in the opposite direction, catalytic ability appears that promotes a chemical reaction in which molecular hydrogen is desorbed from graphene or the like containing adsorbed hydrogen atoms through the loss of hydrogen atoms. It will be. At this time, graphene or the like containing the adsorbed hydrogen atoms becomes a starting material (a material in a hydrogen storage state) that occludes hydrogen.
A catalytic effect that promotes the desorption of hydrogen as a whole appears through a reaction from a deficiency of 5 hydrogen atoms to a deficiency of 3 hydrogen atoms through desorption of hydrogen molecules.

In order to form the atomic vacancies described above by sputtering using an inert gas ion such as the above-mentioned argon ion, a compound having a graphene structure is prepared, an atomic vacancy is formed in the compound, and hydrogenation is further performed. By performing the treatment, a trihydrogen atom defect is formed. The material produced by this method has the autocatalytic ability described above for its use. And the processing method which performs preparation which forms such a 3 hydrogenation atom defect | deletion is called the activation method of autocatalytic ability.

Here, graphene is a two-dimensional sheet-like substance having a thickness of one atom and has a six-membered ring (honeycomb) structure with sp ² carbon. In the present specification, when the above-mentioned honeycomb structure in which sp ² carbons are bonded to each other (hereinafter sometimes referred to as “honeycomb structure”) is present in the carbon-based hydrogen storage material used in the present invention. The structure is called a local graphene-like structure.

That is, the local graphene-like structure is formed of 12 sp ² carbons as a minimum unit, and constitutes a trihydrogen atom-deficient structure at the center thereof. Such a structure is referred to as a V ₁₁₁ structure (see FIG. 1A), and by having this structure, an active barrier during a hydrogen adsorption reaction and / or desorption reaction described later is lowered.

FIG. 1A shows a microscope image obtained by observing an example of the hydrogen storage hydrocarbon compound having the autocatalytic structure described above using a high-resolution scanning tunneling microscope. From this image, it is shown that the hydrocarbon compound has a structure having an atomic deficiency as shown in FIG. 1A, and it is confirmed that this autocatalytic structure exists in nature as a local structure.

Also, the above-mentioned trihydrogen atom-deficient structure is theoretically specified and supported by a theoretical simulation method. Using this theoretical simulation, it is possible to specify the change path of the nuclear positions of the carbon material and hydrogen on the reaction path using an electronic computer, and to determine that the energy does not reach infinity. The reaction path is determined by identifying one path that gives the upper limit of the activity barrier.

From the results of theoretical calculations, by exposing a carbon-based compound having an atom-deficient structure to atomic hydrogen and molecular hydrogen, a tetrahydrogen atom-deficient structure is formed, and the surface of a compound in which hydrogen has a graphene-like structure It is shown that the surface diffusing upward and the trihydrogen atom-deficient structure is formed with high selectivity through this surface diffusion.

Also, experimentally, it has been found that there are coexistence of 4-hydrogen atom deficiency and 3-hydrogen atom deficiency in the carbon-based material, and that hydrogen diffused on the surface of the carbon-based material exists. These experimental and theoretical proofs reveal a method for synthesizing trihydrogen atom defects.

By the way, hydrogen adsorbed on the carbon material as described above is known to cause diffusion on the surface of the material, and depending on the path, the energy barrier for surface diffusion is about 1.5 to 1.7 eV. It is said. The reaction process is adjusted by an external hydrogen partial pressure.

Here, at room temperature (300 K), the transition time required for the hydrogen-based carbon material to be released and the energy barrier at that time (activation enthalpy ΔH, hereinafter referred to as “desorption activation energy”) Is shown in Table 1 below (see Energy, Barriers, and Rates-Transition, State, Theory, For Physicists, D. C, Elton).

As is apparent from Table 1, when ΔH = 1.3 eV, the transition time is 41 years at room temperature, indicating that virtually no reaction occurs. This suggests stability during transportation. On the other hand, although not described in Table 1 above, the transition time at 180 ° C. (500 ° K) is 57 seconds, indicating that hydrogen is easily generated.

By the way, the adsorption / desorption reaction of hydrogen on various carbon-based materials at room temperature will be described below with some examples. First, the adsorption / desorption reaction of hydrogen when toluene is used as the organic hydride is represented by the following formula (1).

In the above formula 1, ΔE represents hydrogen desorption activation energy, and when ΔE> 0, it means that the desorption of hydrogen molecules from methylhexane is an endothermic reaction. When the reaction of the above formula 1 is performed in a vacuum, ΔE is as high as 2.14 eV in actual measurement and 2.68 eV in GGA (Generalized gradient approximation). So you can see that the reaction doesn't really happen. For this reason, unless a small plant equipped with a reaction catalyst is used, although hydrogen can be occluded into toluene to form methylcyclohexane, hydrogen cannot be extracted during the reverse reaction.

On the other hand, when graphene having a V ₁₁₁ structure is reacted with hydrogen at room temperature, the hydrogen adsorption / desorption reaction is represented by the following formula (2).

In the above formula 2, it can be seen that ΔE is a low value of 0.03 eV as calculated by LDA and almost reversible reaction at zero partial pressure, so that hydrogen adsorbed on graphene can be easily taken out.

Further, when an aromatic molecule (VANG: Vacancy-centered hexagonal armchair nanographene) that gives a hydrogen atom defect structure and hydrogen are reacted at room temperature, the following formula (3) is obtained. Here, the molecular structure of VANG is stable as shown in FIG. 2B, and the reaction activity barrier with hydrogen molecules is comparable to that of graphene.

In the case of the above formula 3, ΔE is −0.46 eV, and the sign is opposite to that in the case of the above formula 1 using the organic hydride, and the reaction energy from the hydrogenated state to the hydrogen desorption is exothermic. Presumed to be a reaction. This represents that the autocatalytic ability described later is imparted. Moreover, the active barrier when hydrogen desorbs from the carbon material as described above is approximately 1.3 eV in calculation. This means that it can be transported safely.

An example of a polycyclic aromatic compound having a 3-hydrogen atom deficient structure (V ₁₁₁ ) is shown in FIGS. In FIG. 2A, hydrogen atoms bonded around V ₁₁₁ and hydrogen diffused on the carbon forming the honeycomb structure are separately shown.

FIGS. 3 and 4 show the results of simulation of how trihydrogen atom defects are generated via surface diffusion. Here, after hydrogen is adsorbed to the graphene having the trihydrogen atom deficient structure as described above, the state when the energy is (A) to (E) in FIG. 3 is shown in FIGS. This is shown schematically in E). As shown in FIG. 4 (A), a hydrogen atom is bonded to a certain carbon 1 and then moves to another adjacent carbon 2 and further moves to another carbon 3 and diffuses.

Next, the reaction process of the adsorption / desorption reaction of molecular hydrogen on a carbon-based material having three hydrogen atom deficiencies will be described. First, FIG. 5 shows the reaction of molecular hydrogen to a carbon-based material having a trihydrogen atom deficiency as an estimated value of the active barrier. FIGS. 6A to 6C are schematic diagrams showing how hydrogen molecules are adsorbed in the state of an active barrier in FIG. As shown in these schematic diagrams, it is suggested that a pentahydride deficient structure is formed, and it is clear that the active barrier at that time is just over 1.3 eV.

And looking at the difference in total energy before and after the reaction where hydrogen molecules are adsorbed, it shows only a slight decrease of 0.03 eV. From this, it can be seen that this reaction becomes a reversible reaction because the formation energy of the pentahydrogen atom-deficient structure is extremely small.

Next, the “autocatalytic reaction” in the present specification means that the substance structure itself that stores hydrogen has catalytic ability before and after the reaction that stores hydrogen, and the atoms contained in the structure of the substance. It means that molecular dissociative adsorption is induced with migration (surface diffusion reaction). Specifically, when the above-described trihydrogen atom-deficient structure is present in the local graphene-like substance, the following reaction occurs.

That is, in the process in which one molecule of hydrogen molecule reacts with a trihydrogen atom-deficient structure (reactor process), carbon is adsorbed on the trihydrogen atom-deficient structure, and the carbon system in which the pentahydrogen atom-deficient structure is used. It is formed in the carbon structure of the material, after which hydrogen diffuses on the carbon structure and hydrogen is occluded in the carbon-based material. This reverse reaction occurs when hydrogen is released. And as a result of having the property of “autocatalytic reaction”, it means that the structure having catalytic ability is “recovered” locally even in the reaction product obtained after occlusion of hydrogen.

The above-mentioned autocatalytic ability can be imparted to a carbon-based material as follows, for example, to produce the carbon-based hydrogen storage material of the present invention. Hereinafter, such provision of activity may be referred to as “activation”.

2. Production method of carbon-based hydrogen storage material The carbon-based hydrogen storage material of the present invention comprises: (a1) a step of preparing a production raw material; and (a2) a production raw material set in a container adjusted to have a predetermined gas partial pressure (A3) forming a hydrocarbon compound having an atomic deficiency; (a4) converting the hydrogen in the vessel into atomic hydrogen; and (a5) exposing to atomic hydrogen. It can be manufactured by a method.

As the production raw material used in the above step (a1), graphene or an analog thereof (hereinafter also referred to as “graphene etc.”) can be exemplified. Such graphene and the like can be synthesized as follows. First, nanographene can be synthesized by a method of chemically synthesizing and then activating using a device capable of performing a sputtering process and introducing hydrogen.

Nano graphene molecules (sometimes called polycyclic aromatic hydrocarbons, “PAH”) are synthesized in detail by, for example, precursors such as compound D1 in FIG. 7, compound D2 in FIG. 9, compound D4 in FIG. A nanographene segment can be synthesized by synthesizing and pre-associating the obtained precursor (Reference 1: Acc. Chem. Res., 41, 511-520 (2008).). Further, according to the reaction scheme shown in FIGS. 7 and 8, the C ₆₀ segment shown in the upper part of FIG. 8 can be synthesized from the compound A1 shown in FIG. 7 (Reference 2: Angew. Chem. Int. Ed. 44, 5592 (2005), Reference 3: Angew. Chem. Int. Ed. 37, 2696 (1998)).
According to such a synthesis method, nanographene molecules can be obtained as a powdery sample by treating a sample that has undergone an oxidative cycloaddition reaction in argon gas or the like.

For example, tetraphenylcyclopentadienone (product code T1062, manufactured by Tokyo Chemical Industry Co., Ltd.) and 1,4-bis (trimethylsilyl) -1,3-butadiyne (manufacturer codes 320-49913 or 324-49911) are used as starting materials. And the first Diels-Alder reaction using diphenyl ether to obtain compound B1. Thereafter, nBu ₄ N ⁺ F The above compound A in THF ^- to remove the trimethylsilyl group using, second Diels using diphenyl ether - by Alder reaction to give compound D1 (Figure 7).

Subsequently, C ₆₀ segment 1 can be obtained by a dehydrocyclization reaction using Cu (OSO ₂ CF ₃ ) ₂ / AlCl ₃ / CS ₂ . When the obtained C ₆₀ segment 1 is sputtered with argon ions, C ₅₉ segment 1 is obtained. By adding hydrogen to this C ₅₉ segment 1, C ₅₉ segment 1 having a V ₁₁₁ structure is obtained (FIG. 8). reference).

As another synthesis method, synthesis of C ₆₀ segment 1 using as starting materials dialkyltetraphenylcyclopentadienone (compound A2) and 1,4-bis (trimethylsilyl) -1,3-butadiyne shown in FIG. The C ₆₀ segment having n-C ₁₂ H ₂₅ can be synthesized by the same reaction as that described above. The C ₆₀ segments with resulting n-C ₁₂ H ₂₅ and C ₅₉ segment having a n-C ₁₂ H ₂₅ by sputtering with argon ions, by performing the hydrogenation on the compounds, n having a V ₁₁₁ structure it can be obtained C ₅₉ segments with -C ₁₂ H ₂₅ (FIG. 10).

The synthesis of small single-layer graphene flakes is also described in the references [Nature, 466, 470-473 (2010); Nature, 531, 489-493 (2016); Acc. Chem. Res., 41, 511-520 (2008 )]], A raw material is obtained, and a gold thin film is prepared in a suitable form in a metal container such as stainless steel or a glass container. It can be synthesized by introducing a dibromo-9,9′-bianthracene or the like and performing a heat treatment to increase the temperature. For example, when 9,10-dibromoanthracene as a starting material is polymerized by heating at about 200 ° C., 10,10′-dibromo-9,9′-bianthracene (product of Sigmadrich GK) is obtained. Can do. When the obtained 10,10'-dibromo-9,9'-bianthracene is treated at about 400 ° C., a polymer having a graphene structure is obtained.

Subsequently, this polymer is sputtered with argon ions in the same process as employed in the above method, and then hydrogenated to obtain a polymer having a V ₁₁₁ structure (see FIG. 11). ). By processing the powdered nanographene molecules and small single-layer graphene flakes on the metal surface obtained in this way using a device capable of sputtering and introducing hydrogen, a hydrogen storage material having a V ₁₁₁ structure can be obtained. I can do it.

In addition, by using the starting dendrimer material shown in FIG. 12, a C ₁₃₂ segment was synthesized, sputtered with argon ions in the same process as employed in the above two methods, and then hydrogenated to obtain V C ₁₃₁ segments with ₁₁₁ structure can be obtained.

Second, thin film graphite or a compound having a multi-layered graphene structure was obtained by thermal decomposition using crystalline molecules (molecular crystals) without using a catalyst, and this was cut and peeled by a mechanical method. Later, an atomic defect is formed by a sputtering method, and a hydrogen storage material having a V ₁₁₁ structure can be synthesized by exposure to subsequent atomic (or molecular) hydrogen.

For example, polymerized hydrocarbons such as film-like crystalline polyimide are carbonized by heat treatment in a temperature range of 1,000 to 1,500 ° C, followed by heat treatment in a temperature range of 2,500 to 3,200 ° C. Alternatively, graphene can be obtained to obtain graphene or the like having a thin film graphite or a multi-layered graphene structure (Reference 4: Carbon, 251, 2-10 (2012), Reference 5: Carbon 30, 255-262 (1992) ), Reference 6: Production and technology 66, 88-91 (2014)).
The graphene surface is prepared by peeling the sample thus obtained on the silicon oxide surface, or cutting and peeling by a mechanical method. Thereafter, in order to activate this graphene surface, it is possible to synthesize atomic vacancies by using a sputtering method and subsequently synthesize hydrogen storage materials having a V ₁₁₁ structure by exposure to atomic (or molecular) hydrogen. .

Third, a compound having a nanographene structure can be obtained by a detonation method in which the starting material and reaction conditions are adjusted. This method is suitable for mass production.

Fourth, by supplying a hydrocarbon gas as a raw material onto a metal substrate having a catalytic effect and heating, and synthesizing graphene on the substrate by chemical vapor deposition (CVD), graphene or graphite can be obtained. it can.

At this time, a small single-layer graphene flake can be synthesized by using a single crystal substrate having a high mirror index as the substrate. It has been revealed by photoelectron spectroscopy and high-resolution electron beam energy loss spectroscopy that the nanographene ribbon generally loses its characteristic electronic structure as graphene due to strong interaction with the substrate. By introducing a low molecular species such as hydrogen and migrating between small single layer graphene flakes and a metal substrate, the substrate and small single layer graphene flakes can be decoupled, immersed in an alkaline aqueous solution, or even By performing electrolysis and generating gas such as hydrogen at the substrate-nanographene interface, it is separated from the substrate by adding mechanical effects due to bubbles, transferred to another substrate, etc. to maintain the properties as graphene Small single-layer graphene flakes can be synthesized.

Typically, a single crystal of a metal or a metal compound that can be expected to have a catalytic effect on the decomposition reaction of organic molecules by the contribution of d electrons such as TiC is cut out in the direction of a high index plane, and 1 × 10 ⁻⁷ to 1 × 10 ⁻⁹ Pa After heating to 1,000 ° C. to 2,000 ° C. under an ultrahigh vacuum, an inert gas of 1 × 10 ⁻³ to 1 × 10 ⁻⁵ Pa is introduced and ion sputtering is performed. This process is repeated to clean the surface while confirming the surface structure by low-energy electron diffraction.

If a clean surface with a well-defined high index such as TiC (410) is obtained by this process, a stepped surface structure in which terraces (flat parts) and steps (steps) of about several nanometers appear repeatedly is formed. Can do. Introducing hydrocarbon molecules such as ethylene gas at a pressure of 1 x 10 ^-3 to 1 x 10 ^-6 Pa on a stepped surface structure of the order of several nanometers controlled at the atomic level, By heating at temperatures up to 1,500 ° C, small single-layer graphene flakes with the same width as the terrace are synthesized. According to this method, it is possible to synthesize small single-layer graphene flakes whose width is controlled in units of 1 nm by changing the plane index of the substrate used.

Fifth, after obtaining nanodiamond by detonation method, nanographene can be obtained by a method of converting to nanographene. Nanodiamonds obtained by detonation are nanoparticles composed of a core part having a diamond structure of about 5 nm and a shell part on the surface having an amorphous carbon-like structure. The high-temperature and high-pressure conditions that occur during detonation in a stainless steel sealed container, etc. occur only for a very short time, so that the growth of the diamond structure is suppressed and diamond nano-particles with a relatively uniform particle size distribution are present. Particles (nanodiamond) are obtained.

Nanodiamond originally has a thermodynamically unstable structure in the phase diagram of simple carbon at room temperature and atmospheric pressure, and it is easily relaxed due to the high surface area characteristic of nanoparticles. Since it is easy, it is relaxed to a graphene structure which is a stable structure at room temperature and atmospheric pressure conditions by heating or irradiation with an electron beam or other particle beam.

Nitrogen atoms derived from the nitro group contained in the explosive used for detonation exist as defects in the diamond lattice, and iron contained in the detonation vessel structural material is used as an impurity for amorphous carbon on the nanodiamond surface. It exists in the middle or between the nanodiamond particles, and these are also considered to contribute to the conversion of nanodiamond into nanographene.

Typically, nanographene with a size of several nanometers is easily synthesized by heating nanodiamonds in vacuum or argon or other inert gas atmosphere at a temperature of 1,300 ° C to 1,700 ° C. Can do. At this time, the precursor nanodiamond is dispersed in isopropanol, and a voltage of 1 to 10 V is applied to perform electrophoretic deposition (EPD) for 10 to 100 seconds, and then deposited on a heat-resistant substrate such as graphite. By heating it after heating, a nanographene sample can be obtained in a more dispersible state. In addition, during EPD, an additive such as 1 to 10 mg of iodine or 1 to 10 mg of acetone or water may be added to 100 mg of isopropanol.

Sixth, graphite or nanographene can be obtained from activated carbon fibers (ACFs). The activated carbon fiber is activated carbon obtained by carbonizing and activating a fibrous resin or the like, and its basic structure is a nano graphene structure. A structure in which several layers of nanographene are stacked is called a nanographite domain. Although depending on the synthesis method or processing method, ACFs have a structure in which nanographite domains composed of nanographene of about several nanometers form a three-dimensional random network. Between nanographites, there is a nanospace of the same size as nanographite, so it has a much larger specific surface area (up to 3,000 m ² / g) than normal activated carbon, and its composition It has the feature that most of the carbon atoms are exposed on the surface.

ACFs are synthesized using cellulose, polyacrylonitrile, phenol resin, pitch, etc. as precursors. Cellulose-based ACFs are made of viscose rayon, polyacrylonitrile-based ACFs are made of acrylic fibers, and phenol-based ACFs are made of phenol resin fibers obtained by melt spinning novolac and then curing with formaldehyde in an acidic catalyst. When these precursors are oxidized by heating at 200 to 300 ° C. in an oxidizing gas atmosphere such as air, the molecular structure is changed by the cyclization reaction and becomes infusible. This infusibilized material is carbonized by heating at 600 ° C to 1,300 ° C in an inert gas, and then activated and synthesized by heating at 700 ° C to 1,000 ° C in an atmosphere such as water vapor. To do.

In the case of pitch-based ACFs, a high melting point pitch in which the ratio of liquid crystal components is increased to 55 to 65% by further heat treatment of petroleum pitch than ordinary pitch is used as a precursor. This high melting point pitch is melted and spun by injection or the like. The obtained yarn is heat-treated at 150 ° C to 400 ° C in an oxidizing gas atmosphere to be infusible, then carbonized at 800 to 1,200 ° C in an inert atmosphere, and heated in steam or the like To activate and synthesize.

Here, the graphene is as described above, and the graphene analog includes a graphite-like substance, a carbon nanotube, various fullerenes, and the like having a honeycomb structure in the molecule as an optimum surface area. In the step (a2), these materials are set, and the gas partial pressure in the container is 0.5 × 10 ⁻⁷ to 0.5 × 10 ² Pa (hereinafter, this range is referred to as “vacuum”). )). The reason why the gas partial pressure is in such a range is that the process (a2) is a process prior to the introduction of single atom deficiency by ion beam irradiation in (a3), and the generation efficiency of single atom deficiency is high. is there. Further, this is because the case where a bipolar DC glow discharge sputtering apparatus, a magnetron sputtering apparatus or the like is used in the step (a3) described later is taken into consideration. Note that the gas partial pressure in the step (a2) is not that of hydrogen gas alone but of mixed gas molecules.

Next, in the step (a3), the hydrocarbon compound is irradiated with an ion beam and then annealed to form a hydrocarbon compound having a desired atomic defect structure. Here, the ion beam is preferably obtained by ionizing a chemically inert gas because the characteristics of the substance can be changed while the structure of the carbon-based material is basically maintained. It is preferable to use a beam, a helium ion beam, a krypton ion beam, a xenon ion beam, or the like from the viewpoint of efficient generation of single atom defects and cost.

Further, it is preferable to irradiate the ion ion beam at an ion energy of 80 to 110 eV for 2 to 5 seconds in order to form a desired atomic defect structure. By this irradiation, the desired atomic defect structure is formed. .

The annealing is preferably performed at about 550 to about 600 ° C. from the viewpoint of work efficiency, and more preferably about 600 ° C.

Next, in the step (a4), activating the hydrogen in the container with an arc filament at about 2,000 to 2,400 ° C. is sufficient to hydrogenate the atomic defect structure. It is preferable because hydrogen can be generated. Here, it is preferable that the filament is made of tungsten, molybdenum, or tantalum from the viewpoint of the high thermal dissociation function of hydrogen and the stability of the processing operation. This is because nichrome or iron-chromium wire is not suitable for heating at 2,000 ° C. or higher, and it is considered that hydrogen hardly dissociates at temperatures below 2,000 ° C.

Subsequently, in the step (a5), the hydrocarbon compound having an atomic defect is exposed to activated hydrogen using the arc-shaped filament at about 800 to 1,000 ° C. for about 5 to about 10 minutes. To perform hydrogenation treatment. Further, the hydrogen partial pressure in the container at this time is required to be 0.5 to 2 × 10 ⁻² Pa in order to form a sufficiently isolated V ₁₁₁ structure. By this hydrogenation treatment, atomic hydrogen or molecular hydrogen can be introduced into the atomic defect structure portion formed as described above, and the carbon of the present invention having a V ₁₁₁ structure imparted with autocatalytic ability. Based hydrogen storage materials can be produced.

When such an autocatalytic structure is restored in the final reaction state, hydrogen adsorption and / or desorption occurs in multiple stages. In addition, when at least 4 hydrogen molecules are adsorbed and / or desorbed per atomic deficiency, hydrogen release with exothermic reaction will not occur until V + 3 H_ ₂ <=> V_ ₂₂₂ It is predicted.

There is also a theoretical simulation method that can prove with sufficient reproducibility that the energy on the reaction path does not become infinite for the stable structure of the compounds that constitute the carbon-based material as described above. To do. For this reason, when the existence of a structure is actually identified, it is possible to specify reaction conditions in the presence of hydrogen molecules.

3. Hydrogen storage method and release method using the above carbon-based hydrogen storage material Next, the carbon-based hydrogen storage material of the present invention obtained as described above is placed in a container, and 0.5 × 10 ⁻³ to 15 MPa hydrogen is charged. Occlude. By increasing the pressure at the time of occlusion of hydrogen, a larger amount of hydrogen can be occluded in the carbon-based hydrogen storage material of the present invention.

The carbon-based hydrogen storage material of the present invention in which hydrogen is occluded under the above conditions is occluded by heating at 0.5 × 10 ² to 1.5 × 10 ³ ° C for 0.5 × 10 ⁻⁹ to 0.8 × 10 ⁴ seconds. Hydrogen can be released. As described above, since the carbon-based hydrogen storage material of the present invention has a low active barrier and hardly generates heat when releasing hydrogen, it can be safely and efficiently controlled while controlling the amount of hydrogen released per unit time. Can be taken out.

4). The hydrogen storage device using the said carbon-type hydrogen storage material The structure of the one aspect | mode of the hydrogen storage device of this invention is shown by FIG. As shown in FIG. 13, the hydrogen storage device 100 according to this aspect is configured with (i) the hydrogen storage member 10 constructed with the carbon-based hydrogen storage material obtained as described above, and the substrate material. A flat plate member 15 including a substrate member 13, (ii) a container 20 and a vacuum pump 25, (iii) a pressure control device including a hydrogen supply valve VLa and a hydrogen release valve VLb, and (iv) a temperature control device 30. It has. The hydrogen storage device 100 includes (v) a voltage application device 40, (vi) a vibration device including a vibrator 51 and a vibration control unit 52, and (vii) light irradiation including a light source LS, a converging lens LZ, and a mirror MR. Device. Further, the hydrogen storage device 100 includes (viii) an atomization promoting device including a DC power supply 61 and a tungsten filament 62, and (ix) an overall control device 70.

The container 20 is provided with a hydrogen supply port 20a, a hydrogen discharge port 20b, and an emergency discharge port 20c. The container 20 is provided with a light irradiation window WIN.

The container 20 is a container that can form a sealed internal space in a state where the flat plate member 15 is accommodated. Here, the flat plate member 15 is fixed to a carrier member 19 fixed to the inner surface of the container 20.

In the present embodiment, the substrate member 13 is made of a low activity metal, graphite, alumina, or the like. A flat plate member 15 composed of the substrate member 13 and the hydrogen storage member 10 placed on the substrate member 13 is arranged in the container 20.

Note that the substrate member 13 may be omitted, and only the pellet-shaped hydrogen storage member 10 obtained by molding a powder sample may be disposed in the container 20.

The hydrogen supply port 20a is connected to the hydrogen supply valve VLa via the first hydrogen supply piping member. The hydrogen supply valve VLa is connected to the hydrogen supply device 91 via the second hydrogen supply piping member. Here, the hydrogen supply device 91 changes the hydrogen supply pressure in accordance with the control by the overall control device 70. The hydrogen supply valve VLa adjusts the amount of hydrogen supplied from the hydrogen supply device 91 into the container 20 according to the control by the overall control device 70.

The hydrogen release port 20b is connected to the hydrogen release valve VLb via the first hydrogen release piping member. The hydrogen release valve VLb is connected to the hydrogen release device 92 via the second hydrogen release piping member. Here, the hydrogen release device 92 changes the hydrogen release pressure in accordance with the control by the overall control device 70. The hydrogen supply valve VLb adjusts the amount of hydrogen released from the container 20 to the hydrogen releasing device 92 according to control by the overall control device 70.

That is, the hydrogen pressure in the container 20 is controlled by the hydrogen supply valve VLa, the hydrogen release valve VLb, the hydrogen supply valve 91 in the overall control device 70, and the control function part for the hydrogen release valve VLb and the hydrogen release device 92. A pressure control device is configured.

It should be noted that a mass spectrometer can be adopted as a device for confirming that hydrogen is contained in the gas released from the hydrogen storage member 10. In this apparatus, it is also possible to install in a separate room where the discharge gas can be guided and separated by a gate valve. Alternatively, a mechanism can be provided in which hydrogen in the released gas is separated through a palladium (Pd) film or a palladium tube that can be heated to a higher temperature and led to a separate chamber.

The emergency discharge port 20c is connected to the safety valve VLc via the first emergency discharge piping member. Here, the safety valve VLc is opened when the measurement result of the pressure in the container 20 by the pressure gauge (PG) exceeds a predetermined value. And even if hydrogen is discharged | emitted via the 2nd emergency discharge piping member, the gas which passed through the safety valve VLc will be discharge | released to the safe exterior.

Note that the overall control device 70 may acquire the measurement result of the pressure in the container 20 by the pressure gauge (PG) and refer to the pressure control in the container 20.

In this embodiment, a vacuum pump 25 is further provided. By using the vacuum pump 25 under the control of the overall control device 70, the inside of the container 20 can be maintained in a high vacuum environment under dry conditions.

As the vacuum pump 25, a turbo molecular pump, an ion pump, a titanium pump, or the like can be used.

The temperature control device 30 has a heating function and a cooling function. The temperature adjusting device 30 controls the temperature in the container 20 according to the control by the overall control device 70. A thermometer may be arranged in the container 20, and the temperature control device 30 may refer to the measurement result of the thermometer when performing temperature control. Further, the temperature control device 30 may report the measurement result of the thermometer to the overall control device 70, and the overall control device 70 may refer to the temperature control device 30 when controlling it.

The DC power supply 61 controls the current flowing through the tungsten filament 62 according to the control by the overall control device 70. When a current flows through the tungsten filament 62, the tungsten filament 62 is heated. When the tungsten filament 62 heated to such a temperature is irradiated with hydrogen gas through the hydrogen supply port 20a and the third hydrogen supply pipe, hydrogen atomization (activation) is promoted and then the hydrogen storage member 10 is accelerated. Irradiate toward.

When such a hydrogen storage device 100 is used, the pressure control device performs pressurization control while the inside of the container 20 is in a hydrogen atmosphere, and the temperature control device 30 controls the temperature in the container 20, whereby hydrogen is supplied to the hydrogen storage member 10. Is occluded. As shown in Table 1 above, the active barrier of the carbon-based hydrogen storage material of the present invention is estimated to be about 1.3 eV, so that hydrogen is stably stored at room temperature. 10 is not released. For this reason, hydrogen generated as a by-product in an oil refinery factory or other factories can be stored in the hydrogen storage device and transported or transported safely to a desired location.

Further, when releasing the hydrogen stored in the hydrogen storage member 10 stored in the container 20, it is preferable to perform the following procedure in order to ensure safety. Initially, the container is heated and controlled by the temperature control device 30 at normal pressure to release the hydrogen stored in the hydrogen storage member 10. After the hydrogen release is started, the temperature control by the temperature control device 30 is performed. To control the hydrogen release rate.

The release of hydrogen from the hydrogen storage device 100 of the present invention increases remarkably even at about 100 ° C. For this reason, the apparatus used for temperature control does not need to be a thing only for this device, You may use the heat source currently used widely. By performing the temperature control and pressure control as described above, the hydrogen occluded in the device can be safely taken out from the device at the transport destination or the transport destination.

The hydrogen storage device 100 further includes a voltage applying device 40 that applies a voltage between both surfaces of the flat plate member 15. It is preferable that the voltage application device 40 can reverse the polarity of the applied voltage in order to appropriately control the occlusion and release of hydrogen. For example, when the gate potential is negative, hydrogen storage in the hydrogen storage member 10 is promoted. Conversely, when the gate potential is positive, the release of hydrogen from the hydrogen storage member 10 is promoted.

Here, the “negative gate potential” means that the potential of the gate electrode installed on the back surface of the substrate member is relatively negative with respect to the carbon-based hydrogen storage material, thereby being positive with respect to the carbon-based hydrogen storage material. Injecting holes. The “positive gate potential” means that the potential of the gate electrode installed on the back surface of the substrate member is relatively positive with respect to the carbon-based hydrogen storage material, so that electrons are Injecting.

The voltage application device 40 is electrically connected to the flat plate member 15 by a wiring member that passes through the wall of the container 20.

The hydrogen storage device 100 further includes a vibration device that vibrates the flat plate member 15. As described above, the vibration device includes the vibrator 51 on the surface of the hydrogen storage member 10 in the flat plate member 15 and the vibration control device 52. The vibrator 51 vibrates according to the vibration control signal supplied from the vibration control unit 52 that operates according to the control by the overall control device 70. Examples of the vibrator 51 include a SAW oscillator, a crystal vibrator, a ceramic oscillator, and the like, and it is more preferable to use a laser beam excitation ultrasonic generator.

The vibration control unit 52 is electrically connected to the vibrator 51 by a wiring member that passes through the wall of the container 20.

Further, the hydrogen storage device 100 further includes a light irradiation device that irradiates the surface of the hydrogen storage member 10 in the flat plate upper member 15 with light for external field. For this reason, the selective hydrogen desorption reaction by the resonance local vibration excitation which suppressed the temperature rise generation | occurrence | production of the whole device is accelerated | stimulated.

The light irradiation device includes the light source LS, the converging lens LZ, and the mirror MR as described above. The laser light source LS emits light according to control by the overall control device 70. Here, the light is preferably irradiated with light selected from the group consisting of infrared light, terahertz light, visible light, ultraviolet light, and laser light in terms of accelerating the release of hydrogen. External light or terahertz light is more preferable because the degree of acceleration is high.

Here, the light emitted from the light source LS is irradiated and reflected on the mirror MR via the converging lens LZ. Then, the light reflected by the mirror MR is irradiated onto the surface of the hydrogen storage member 10 through the light irradiation window WIN.

By using the hydrogen storage device 100 configured as described above, hydrogen can be efficiently stored, and can be safely stored and transported.

In the hydrogen storage device 100 described above, since the voltage application by the voltage application device 40 and the light irradiation by the light irradiation device are performed, the material of the substrate member 13 is a semiconductor material. On the other hand, when applying the vibration by the vibration device without performing the voltage application by the voltage application device 40 and the light irradiation by the light irradiation device, the material of the substrate member is metal, insulator, glass, It can be either.

Further, when neither voltage application by the voltage application device 40, light irradiation by the light irradiation device, nor vibration application by the vibration device is performed, the material of the substrate member is a mesh-like metal plate, It can be set as the form hold | maintained (or the form inserted | pinched). Further, the substrate member may be a silicon substrate subjected to oxidation treatment or the like, and may be held on the silicon substrate by electrostatic attraction or the like. In addition, when activated to a general carbon material, since it is a solid sample, it can be retained on a metal, insulator, glass, etc., which has low degradation reactivity due to hydrogen gas, In order to prepare for the progress of the reaction, a metal material is considered preferable from the viewpoint of durability and workability.

In the hydrogen storage device 100 described above, a thermally activated reaction path is applied in the autocatalytic reaction. On the other hand, the reaction activity is expected to increase due to molecular vibration and lattice vibration due to external stimuli other than temperature. The origin of external stimuli other than such temperatures includes electromagnetic waves, ultrasonic waves, electron waves (electron beams), and various particle beams.

Molecular vibrations and lattice vibrations excited by external stimuli other than temperature include (i) molecular vibrations and lattice vibrations coherently excited by electromagnetic fields in the infrared region, and (ii) local electrons by electromagnetic fields from visible light to the ultraviolet region. Molecular vibration / lattice vibration caused by excitation, (iii) Molecular vibration / lattice vibration excited by introduction of ultrasonic waves, and (iv) Molecular vibration / lattice vibration excited as a result of electron beam irradiation or particle beam irradiation Can be mentioned. Here, it is possible to improve the activity more efficiently than thermal excitation by specifying a local mode and exciting molecular vibration and lattice vibration that are directly linked to a chemical reaction.

Such vibrational excitation, at the time of occlusion of hydrogen, vibrationally excited molecular hydrogen itself, the vibrational excitation of the atomic structure in the V ₁₁₁ structure, vibrational excitation of graphene surface portion is associated. In addition, when hydrogen is released, vibration excitation of the atomic structure in the V ₂₂₁ structure and vibration excitation on the surface of hydrogenated graphene are related.

In addition, it is possible to selectively cleave the interatomic bond of hydrogen molecules by irradiating the electromagnetic wave from the visible light to the ultraviolet region of (ii) described above. This is a method for improving the reaction activity when storing gaseous hydrogen molecules. In order to obtain the same effect, a method using a metal catalyst surface that converts hydrogen molecules into atomic hydrogen in advance, or a method using electron beam irradiation or particle beam irradiation that has an effect of dissociating molecules in the gas phase is used. Also good.

FIG. 14 schematically shows an energy diagram related to hydrogen storage / release in nanographene VANG. As shown here, from the state where the desorbed molecules are in the gas phase, the active barrier for causing adsorption is 1.3 eV, and the active barrier for causing migration to the surface is slightly lower than this. It is low.

From this, it can be seen that if there is sufficient temperature and gas partial pressure, adsorption and surface diffusion of hydrogen molecules occur. In addition, when hydrogen is introduced in the form of atoms, an adsorption state equivalent to the on-top type adsorption state on the graphene surface appearing after the surface diffusion can be directly configured. In this adsorption state, the energy is higher than in the desorption state. Therefore, if the temperature is increased sufficiently to exceed the active barrier, which is about 1.2 eV or less, the hydrogen molecules are absorbed by this hydrogen adsorption. Released from VANG. In addition, the excessive hydrogen adsorption to the armchair end of the molecule that is relatively stable may not reach due to migration. From the above, it is considered that the principle of occlusion / release is guaranteed from the simulation results.

In the initial (first) stage in which adsorption of hydrogen molecules to the V ₁₁₁ structure occurs, a reaction with a single active barrier that leads to the formation of the V ₂₂₁ structure proceeds. Thereafter, a migration process having a plurality of active barriers occurs, and dissociative adsorption as a whole on the graphene surface proceeds. At this time, FIG. 14 shows that the energy required in the migration process does not exceed the energy required for the first stage reaction. This leads to the conclusion that migration continues from the initial reaction.

After the adsorption proceeds, when the energy to the molecular vibration is dissipated and the stable state is reached, the molecule where the hydrogen adsorption occurs has a structure having some kind of energy minimum point. At that stage, the structure becomes stable, so that the adsorbed hydrogen does not easily return to the gas phase. When on-top adsorption occurs in this way, a process in which hydrogen adsorbed on individual carbon forms molecular hydrogen and desorbs in the gas phase is extremely difficult to occur.

When the temperature of the hydrogenated VANG in a stable hydrogen storage state is raised, hydrogen migration over the active barrier is reactivated as a result of thermal oscillation. At this time, a local V ₂₂₁ structure which is one of energy minimum points is generated. When this structure appears, the elimination reaction of hydrogen occurs through an active barrier that is relatively easy to handle, such as about 1.2 eV. The barrier immediately before desorption is slightly larger than that required for the hydrogen migration process on the molecule. From the above, the temperature range from 100 ° C to 250 ° C, which is a temperature range sufficient to exceed the 1.3 eV active barrier, is necessary for desorption from VANG in the hydrogen storage state. It can be estimated as active energy.

From the above, the hydrogen storage material of the present invention is a hydrogen storage hydrocarbon compound composed only of carbon and hydrogen, and has a structure that causes a local autocatalytic reaction (hereinafter, referred to as “autocatalytic structure”). ) Is theoretically supported.

Hereinafter, the present invention will be described in more detail with reference to examples. The present invention is not limited to the following examples.
(Example 1) Production of carbon-based hydrogen storage material of the present invention As the carbon-based material (graphene material) having a graphene-like structure, quiche graphite or highly oriented pyrolytic graphite (HOPG) was used. As these graphene materials, commercially available products may be used. This graphene material was set at the sample mounting position in the trihydrogen atom deficient structure synthesizer. As the 3-hydrogen atom deficient structure synthesizer, a commercially available product may be used.

First, a sample is put in a UHV chamber, and an ion energy of 100 eV is used using an argon ion irradiation device of a scanning probe microscope (SPM) manufactured by JEOL Ltd., which is mounted in a 3-hydrogen atom deficient structure synthesizer. The graphene sample was prepared by irradiating the graphene material with an argon ion (Ar ⁺ ion) beam for an irradiation time of about 3 to about 4 seconds to form a single atomic defect in the outermost layer of the sample. Next, the graphene sample was annealed at 600 ° C. to remove excess adsorbents between atomic defects.

Using a high-resolution scanning tunneling microscope (STM) in constant current mode with a reference pressure of 6 × 10 ⁻⁹ Pa using a JSPM-4500S system (manufactured by JASCO Corporation) under UHV conditions at room temperature This graphene sample was observed. STM tips were prepared by electrochemical etching of tungsten wire and cleaned by Ar ⁺ ion sputtering (ion energy = 1.0-3.5 keV). The imaging conditions were U = 0.1 V and I = 0.4 nA. As a result, it was confirmed that a sufficiently isolated single atom defect structure was formed.

After completion of the annealing, the hydrogen partial pressure in the container containing the annealed graphene sample is set to 10 ⁻² Pa and the arcuate tungsten wire (model number: W-461327) manufactured by Nicola is heated to 2,200 ° C. Atomic hydrogen was generated from hydrogen in the container.

Next, the graphene sample was heated to a temperature of 900 ° C. ± 100 ° C. and exposed to atomic hydrogen for 5 to 10 minutes to hydrogenate the graphene sample to obtain an activated sample. Further, the temperature was adjusted to 600 ° C. and annealing was performed for 2 hours, followed by observation using STM under the same conditions as described above. The observation result is shown in FIG. This microscopic image revealed that the activated sample had an atomic defect structure.

FIG. 15 shows an STM image showing typical atomic defects after sputtering. In performing this experiment, a HOPG sample with Bernal (AB) stacking was used. First, a sample was placed in a UHV chamber, and Ar ⁺ ions were irradiated at 100 eV for 3 to 4 seconds to form a single atomic defect in the outermost layer of the sample. Subsequently, annealing was performed at 600 ° C. in the same manner as described above to remove excess adsorbents between atomic defects. An STM experiment was performed in a constant current mode using a JSPM-4500S system (JEOL) at room temperature and under the same conditions as above with a reference pressure of 6 × 10 ⁻⁹ Pa. STM tips were prepared by electrochemical etching of tungsten wire and cleaned by Ar ⁺ ion sputtering (ion energy = 1.0-3.5 keV). The imaging conditions were U = 0.1 V and I = 0.4 nA. FIG. 15 (d) shows the STM topographic line profile across the unpassivated atomic defect. From this profile, it was confirmed that atomic defects were caused by Ar ⁺ ions.

Next, the above graphite surface was exposed to hydrogen atoms generated by decomposing hydrogen molecules with an arc-shaped tungsten filament (filament temperature 2,200 ° C.) under UHV conditions. The total hydrogen pressure in the UHV chamber was 10 ⁻² Pa using leak valve technology. The material temperature was maintained at 900 ° C. ± 100 ° C. The exposure time was 5 to 10 minutes, and the distance between the sample surface and the filament was 5 to 10 mm. Under these conditions, an on-top adsorption structure of hydrogen was formed over the entire graphene structure on the sample surface.

A single atomic defect was formed under these conditions, but if the exposure time is increased or the exposure time is increased and the sample-filament distance is shortened, typical polyatomic defects (nano-sized pits) are formed. Formation was observed (see FIGS. 15A to 15C).

After hydrogenation of this sample, it was annealed again at 600 ° C. under UHV conditions. Using these samples, STM observation was performed at room temperature, and the same STM image as that shown in FIG. 1B was obtained. Therefore, it was confirmed that the desorption reaction of adsorbed hydrogen proceeds by annealing, and the desorption of other adsorbed hydrogen occurs, leaving only the trihydrogen atom deficiency.

(Example 2) Examination of physical properties of activated sample (1) Preparation of small single layer graphene flakes Graphene flakes prepared by adjusting from graphene material are placed on the Si substrate surface covered with SiO ₂ layer, and micromechanical peeling Thus, single-layer graphene flakes having a width of 3 μm were prepared (see FIG. 8).

FIG. 16 (a) shows an optical microscope image of single-layer graphene flakes as formed on a Si substrate covered with a 285 nm thick SiO ₂ layer. It can be seen that the single-layer graphene flakes (black arrows in the figure) are located at the center of the image together with thicker flakes (white arrows in the figure). FIG. 16B is an optical microscope image of the same single-layer graphene flakes after the Au / Cr electrode is attached by photolithography. A Cr adhesion layer was brought into direct contact with a sample having a thickness of less than 5 nm, and Au was deposited on Cr.

(2) Fabrication of FET When fabricating the FET, a silicon oxide film (SiO ₂ layer) formed on n-type doped-Si was prepared. Micropatterning was performed on the single-layer granfen produced on the substrate, and arbitrary patterning was performed. Graphene with an arbitrary pattern isolated by micromechanical peeling is placed on a SiO ₂ / doped-Si substrate to form a structure, and metal electrodes (source and drain) are attached by lithography to produce a field effect transistor (FET) did. FIG. 17 is a cross-sectional view of the structure thus obtained, and FIG. 18 schematically shows a cross-sectional view of the FET.

Here, doped-Si has a large amount of doping and has conductivity. For this reason, doped-Si is used as the back gate. By applying the back side gate voltage V _bg , the Fermi energy of graphene can be controlled as a capacitor.

(3) Measurement of physical properties of FET FIG. 19 shows the V _bg dependence of a graphene sample measured at room temperature. Black dots indicate data for the original sample. The measurement data after irradiation with 100 eV Ar ⁺ for 5 minutes is indicated by open dots. After exposure to atomic hydrogen for 5 minutes, open square values were obtained. Here, atomic hydrogen was generated by introducing hydrogen gas at 1.0 × 10 ⁻⁵ Torr and heating with a tungsten filament.

FIG. 20 shows the V _bg dependence of the graphene sample irradiated with Ar ⁺ . When this dependence estimated from the results fit to the theoretical equation atomic defect density n _d a was ^{_{n d ~ 9 × 10 12 cm}} -2. The formation of atomic defects dramatically changed the backside gate voltage dependence. The point where the back gate voltage dependency gives the minimum conductivity provides a charge neutrality point (V _CNP ).

From the experiment of FIG. 19, a significant change in the charge neutralization point V _CNP due to the result of hydrogen adsorption was observed as follows. In the original sample, V _CNP was approximately -13 V, but after Ar ⁺ beam irradiation it was -19 V. This variation was thought to be due to the removal of residual contamination by Ar ⁺ irradiation. Subsequent exposure to hydrogen atoms left V _CNP outside the sweep range of the backside gate voltage V _bg (-50 V to +50 V). This negative shift of V _CNP corresponds to the occurrence of electron donation to the graphene sample due to atomic hydrogen adsorption.

The electron mobility was given from the gradient when the backside gate voltage V _bg was in the range of −50 V to 0 V, but was almost equivalent to that of the Ar ⁺ irradiated sample. The mobility of both traces was approximately 2.0 × 10 ³ cm ² V ⁻¹ s ⁻¹ .

Next, the graphene sample after being adjusted by irradiation with Ar ⁺ was exposed to hydrogen molecules at 1.0 × 10 ⁻⁶ Torr for various times. A backside gate voltage V _bg was applied during the exposure. Immediately after turning off the gate voltage and discharging the hydrogen, the conductivity of the sample was measured for the combination of the backside gate voltage V _bg and the exposure time.

FIG. 21 shows that V _bg = +30 V and the original graphene sample was exposed (solid line), 5 minutes (dotted line), 10 minutes (dashed line), 15 minutes (dashed line), and 30 minutes (dashed line). The back side voltage dependence of conductivity when exposed to hydrogen molecules is shown.
FIG. 22 shows the results when the same sample was processed in the same procedure except that the back side gate voltage Vb _g was −30 V. Here, a decisive difference was confirmed. When the sample was doped with V _bg > V _CNP , the charge neutralization point V _CNP did not shift (see FIG. 21). In contrast, when the sample was hole-doped with V _bg > V _CNP , the charge neutralization point V _CNP shifted significantly in the negative direction in response to donation of electrons to the material (see FIG. 22).

Furthermore, as a result of repeating the measurement of conductivity, it was revealed that the charge neutralization point V _CNP returns to the initial position. This indicates that electron donation has disappeared spontaneously. Interestingly, the observed electron donation was the opposite of the case of oxygen molecules (which cause hole donation). Hall donor by oxygen, to be induced by V _bg> V _CNP, to be inhibited in and V _bg <V _CNP revealed. This was the opposite of exposure to hydrogen molecules. Furthermore, hole donation by exposure to oxygen molecules does not spontaneously disappear, as untreated samples exhibit the characteristic of being normally hole doped in conductivity.

From the above, it was shown that the electrical characteristics of the graphene having an atomic defect of the present invention are changed by the hydrogenation treatment.

(4) Evaluation of maximum hydrogen adsorption amount and desorption amount When the sample is occluded with atomic hydrogen, an on-top type hydrogen adsorption structure is formed. This is formed for every two carbon atoms appearing in the graphene structure, and the density of adsorbed hydrogen is n _H ^˜2 × 10 ¹⁵ cm ⁻² . Since the density of atomic vacancies is n _d -9 × 10 ¹² cm ⁻² , maintaining the temperature at 600 ° C. for 0.8 × 10 ⁴ seconds, except for the slight hydrogen remaining in the 3-hydrogen atom vacancy structure, is approximately 99% It was confirmed that the adsorbed hydrogen can be desorbed.

The present invention is useful in the energy field, and is particularly useful in the storage of hydrogen and its center, and the formation of a hydrogen circulation infrastructure.

DESCRIPTION OF SYMBOLS 10 ... Hydrogen storage member 13 ... Substrate member 15 ... Flat plate member 19 ... Supporting member 20 ... Container 20a ... Hydrogen supply port

20b ... Hydrogen discharge port 20c ... Emergency discharge port 25 ... Vacuum pump 30 ... Temperature control device 40 ... Voltage application device 51 ... Vibrator 52 ... Vibration control unit

61 ... DC power supply 62 ... Tungsten filament 70 ... Overall control device 91 ... Hydrogen supply device 92 ... Hydrogen release device LS ... Light source LZ ... Converging lens

MR ... Mirror VLa ... Hydrogen supply valve VLb ... Hydrogen release valve VLc ... Safety valve WIN ... Light irradiation window

Claims (20)

1. A carbon-based hydrogen storage material having an atomic deficiency, which is a hydrogen storage hydrocarbon compound that has self-catalytic ability and releases hydrogen stored in the compound without endothermic heat or releases heat.
2. The carbon-based hydrogen storage material according to claim 1, wherein the hydrogen storage hydrocarbon compound is composed of only carbon and hydrogen.
3. The carbon-based hydrogen storage material according to claim 1, wherein the atomic deficiency has a V ₁₁₁ structure.
4. The carbon-based hydrogen storage material according to claim 1, wherein the hydrogen storage hydrocarbon compound is graphene or nanographene having a V ₁₁₁ structure.
5. Wherein, graphene or nanographene having a V ₁₁₁ structure, C ₅₉ segments are of one selected from the C ₅₉ segments, and the group consisting of C ₁₃₁ segments with an alkyl group, a carbon-based hydrogen according to claim 4 Storage material.
6. 2. The carbon-based hydrogen storage material according to claim 1, wherein a dissociative adsorption activity barrier in the hydrogen storage hydrocarbon compound is less than 2 eV.
7. The carbon-based hydrogen storage material according to claim 6, wherein a dissociative adsorption activity barrier in the hydrogen storage hydrocarbon compound is 1.3 eV or less.
8. The carbon-based hydrogen storage material according to claim 1, wherein the hydrogen storage hydrocarbon compound is capable of storing and releasing two or more hydrogen molecules per catalytic active point.
9. A method for producing a carbon-based hydrogen storage material having atomic defects, comprising:
   Preparing a hydrocarbon compound that is a raw material for producing a carbon-based hydrogen storage material;
   Setting a production raw material in a container having a partial pressure of a gas showing a reaction activity with a hydrocarbon compound of 0.5 × 10 ⁻⁷ to 0.5 × 10 ² Pa;
   Irradiating the hydrocarbon compound with an ion beam and annealing at 550 to 650 ° C. for 2 to 5 seconds to form a hydrocarbon compound having an atomic defect;
   Activating hydrogen in the vessel with an arc filament at 2,000 to 2,400 ° C .;
   Exposing the hydrocarbon compound having an atomic defect to the activated hydrogen at 800 to 1,000 ° C. for 5 to 10 minutes;
   With
   The production of the carbon-based hydrogen storage material having an atomic deficiency is a hydrogen storage hydrocarbon compound that has a self-catalytic ability and releases the hydrogen stored in the compound without endothermic or releases it while generating heat. Method.
10. The production method according to claim 9, wherein the hydrocarbon compound is graphene or an analog thereof.
11. 10. The manufacturing method according to claim 9, wherein the ion beam is selected from the group consisting of an argon ion beam, a helium ion beam, a krypton ion beam, and a xenon ion beam.
12. The manufacturing method according to claim 11, wherein the argon ion beam is irradiated at 80 to 110 eV for 2 to 5 seconds.
13. 2. A hydrogen storage method, wherein the carbon-based hydrogen storage material according to claim 1 stores hydrogen at 0.5 × 10 ⁻³ to 15 MPa.
14. 2. The carbon-based hydrogen storage material according to claim 1, wherein hydrogen is occluded at 0.5 × 10 ⁻³ to 15 MPa, and is heated at 0.5 × 10 ² to 0.5 × 10 ³ ° C for 0.5 × 10 ⁻⁹ to 0.5 × 10 ³ seconds. A method for releasing hydrogen from a carbon-based hydrogen storage material.
15. A hydrogen storage member constructed of the carbon-based hydrogen storage material according to claim 1;
    A container having a hydrogen inlet / outlet and capable of forming a sealed internal space in a state in which the hydrogen storage member is accommodated;
    A pressure control device for controlling the pressure in the container;
    A temperature control device for controlling the temperature in the container; and a safety valve at the hydrogen inlet / outlet,
    Hydrogen storage device.
16. The hydrogen storage device according to claim 15, wherein the pressure control device controls the pressurization and the temperature control device controls the temperature in the container to cause the hydrogen storage member to store hydrogen. device.
17. The pressure control device sets the inside of the container to normal pressure, controls the heating inside the container to start the release of the hydrogen stored in the hydrogen storage member, and after the start of the release, the temperature control device The hydrogen storage device according to claim 15, wherein the device controls a temperature inside the container to control a release rate of hydrogen occluded in the carbon-based hydrogen storage material.
18. The apparatus further comprises a voltage applying device that applies a voltage between both surfaces of the flat member made of the carbon-based hydrogen storage material and the substrate material, and the voltage applying device can reverse the polarity of the applied voltage. Item 16. The hydrogen storage device according to Item 15.
19. The hydrogen storage device according to claim 18, further comprising a vibration device that vibrates the flat plate member.
20. 20. The hydrogen according to claim 19, further comprising an irradiation device that accelerates the release of hydrogen by irradiating the flat plate member with any one selected from the group consisting of electromagnetic waves, ultrasonic waves, and particle beams. Storage device.

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